1. Field of the Invention
The present invention relates to an electric connector configured so that a signal transmission medium inserted in a connector main body is easily held by a lock member.
2. Description of the Related Art
Conventionally, an electric connector for electrically connecting a signal transmission medium, such as a flexible flat cable (FFC) or a flexible printed circuit (FPC), to a circuit wiring board in various electric apparatuses and others has been widely adopted. This electric connector is mounted, for example, via a board connection leg part (a hold-down) soldered to a circuit wiring board so that a connector main body rises upward from the surface of the circuit wiring board and, with the signal transmission medium being inserted inwardly from an insert opening provided at an upper end of the connector main body of the electric connector, electric connection is made.
The signal transmission medium to be inserted in the electric connector in the above-described manner has a terminal portion on an insertion side formed with a positioning part composed of, for example, a notched concave part. In this structure, with a lock member provided on an electric connector side being engaged in this positioning part provided on a signal transmission medium side, the state of insertion of the signal transmission medium is held. For example, in Japanese Unexamined Patent Application Publication No. 2001-196130, a structure is adopted in which, in order not to use a slider for obtaining contact pressure between a contact group held in the connector main body and the signal transmission medium (FPC/FFC), a lock lever is pivotally attached so as to prevent drop-off of the signal transmission medium even with a small contact load.
In this case, however, since the lock member provided to the connector main body is molded as a separate member, the number of components is increased. For this and other reasons, the entire connector tends to be expensive. Moreover, since the structure is such that the lock member is engaged under its own weight with the signal transmission medium side, it is disadvantageously impossible to achieve sufficient power of holding the signal transmission medium.
Furthermore, in another electric connector described in Japanese Unexamined Patent Application Publication No. 2003-100370, a reinforcing fitting to be mounted on both ends of a housing and soldered to a circuit wiring board is provided with an elastic supporting piece elastically pressing and supporting a signal transmission medium (FPC/FFC), thereby allowing prevention of a positional shift of the signal transmission medium and others. However, since the acting direction of the pressure force by the elastic supporting piece and a soldered part of the reinforcing fitting have a positionally shifted relation, if the release operation of the lock member is repeated again and again, an influence occurs to the mount state of the connector main body and others due to a release operation force continuously added to the connector main body, thereby possibly causing the electric connection to be unstable.